so you mean highest NRR would protect ears most?
what is the highest NRR ear muffs come in?

The highest NRR rated ear muffs I could find on the internet was Pro-Ears Ultra 33 Earmuffs (NRR 33 dB). These do not have electronics.
The highest rated electronic ear muffs I could find on the internet was the Pro-Ears Pro Mag Gold NRR 33 Electronic Ear Muffs (NRR 33 dB) over $300 retail.

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